The Flu Busters

By Laurel-Lea Shannon

It’s flu season again, and don’t I know it. While putting together this newsletter I’ve been fighting a flu bug that my partner has had for ten days. What’s worse is that we have plans this weekend to cross-country ski in beautiful Gatineau Park,Quebec. What to do? A friend tells me she takes lots of vitamin D and she never gets the flu. Hmmm. . .

Why does the flu break out every winter, but leave everyone unscathed during the summer? It turns out I’m not the only one asking that question. Japanese researchers recently conducted the first drug-style clinical trial of vitamin D, giving large doses of it to children to test how effective it is in preventing the flu. It turns out vitamin D is a flu-busting dynamo.

Children who were given 1200 IU of vitamin D had a 42% reduction in influenza A—the most severe form of flu (body aches, fever etc.)—compared with the control group. But that’s not all. They also had fewer asthma attacks.

One of the theories about why the flu is so virulent in winter months is that people who live in more northern latitudes, such as Canada and the northern US, experience wild fluctuations in vitamin D throughout the year. In the summer months, when your skin is exposed to ultraviolet light, your body produces high amounts of it. But in the fall and winter your vitamin D levels tank, leaving you susceptible to flu viruses. Low vitamin D levels are also implicated in a host of chronic ailments, and diseases such as cancer and multiple sclerosis.

Although more studies need to be done to understand the role vitamin D levels play in illness and disease, Mitsuyoshi Urashima, the lead researcher in the study, isn’t waiting. He now takes 3000 IU of vitamin D year round and hasn’t had a cold or flu since.

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